Content management systems (CMS), document management systems (DMS) and data management systems refer to systems for managing electronic documents. In the present disclosure the term “document management system” is a general term referring also to content and data management systems. Such systems comprise various features for managing electronic documents, e.g. storing, versioning, indexing, searching for and retrieval of documents. It is appreciated that there are both dynamic and static document management systems. The difference between dynamic and static systems is the way they store files. In the static systems files are stored e.g. in a constant treelike hierarchy that defines relationships for folders and documents stored in the tree. In the dynamic systems the files may be given identifications that define their existence in the system. The location of the files is not constant, but may vary in a virtual space depending on the situation.
In a dynamic document management system, virtual folders are used for enabling browsing of documents (i.e. objects). When a folder hierarchy is navigated, virtual folders comprising documents matching the conditions of the previous levels are dynamically formed. Virtual folders are based on the metadata of the objects (i.e. information on a objects' properties). An example of this is shown in FIG. 1. For example, a user interface view “Documents by Client” 100 shows virtual folders on the basis of the Client property of the documents: “CompanyA”, “CompanyB”, “FirmC”, “OrganizationD” etc. To put it more clear, the documents are listed in a client-specific manner so that when a user selects e.g. “Company B”, s/he is shown a list of documents having “Company B” as their Client property. This is called a direct reference or direct metadata.
It has been realized in this technical field that more versatile and more effective method is needed for querying documents and for forming virtual folders. This invention is addressed to such a need.